Adhesive



Patented Dec. 9, 1941 ADHESIVE Edward F, Christopher and Frank D. DeBeukelaer, Chicago, Ill.

No Drawing.

Application December 24, 1938,

,. Serial No. 241,705

Claims. (Cl. 106-125) This invention relates to an improved animal glue,glue-like substance, gelatin or mixtures'of these materials.

One of the objects of this invention is to provide a glue substancewhose original flexibility and prompt remoistening properties-are notadversely afi'ected, although the products may be held for longperiods'of storage.

Another object oi this invention is to provide a glue substance whichpossesses the property of rapidly resetting after application ofmoisture.

Other objects and advantages of this invention will become apparent fromthe following description and claims.

In the manufacture of a wide variety of articles, a base material, suchas paper, cloth and the like, is provided with a coating of a gluesubstance. In such products as gummed tape the ideal properties of aglue substance coating are .more or less conflicting. For such uses, itis desired that the glue substance'possess a property of retaining itsoriginal flexibility and prompt remoistening value over long periods ofstorage. It is also desired that such a coating shall have a very rapidresetting property after application 01' moisture to the coating.

The term hygroscopic is employed to designate the property of the glueto absorb moisture from the atmosphere in such quantities that the gluebecomes tacky. The term prompt remoistening value" is employed todesignate the property of theglue to take up water on application Kdirectly to the surface of the glue and to pass into colloidal solution.

It has been proposed to prepare glue substances for such purposes by theaddition of hygroscopic materials, such as glucose, sugar, glycerin orcombinations of these materials. In the preparation of glue substancesby the addition of such hygroscopic materials, such large amounts of thematerials are necessary to produce the desired flexibility andremoistening valuesthat the products possess the undesirable property ofbecoming very tacky in moist or humid weather. In the case 01' gummedtape, for example, in moist or humid weather, an adhesive layer preparedwith such hygroscopic materials becomes sufliciently tacky to adhere itto the uncoated side of the paper in the roll,'or in the stack it thetape is in sheet form.

groscopic when dried. In practicing the invention therein disclosed,quantities of the reagent are added to impart the desired properties.

The present invention contemplates the addition of small amounts ofurea, or urea derivatives, such as biuret, to dry glue after the gluehas been ground, or the addition of small amounts of the reagents to theglue-liquor during the process of manuiacture. The quantity oi. reagentadded to the glue is within a range which is below the range employed inthe process disclosed in Patent No. 1,950,483. The amount of reagentadded to, the glue is a small amount sui- In our Patent No. 1,950,483 wedisclose the use oi urea and urea derivatives in the preparation ofadhesives from animal glue to impart to the animal glues the propertiesof existing in a liquid state at ordinary temperatures and of beinghyflcient to impart the desired properties, but is insufficient toimpart the properties of existing in a liquid state at ordinarytemperatures and 0! being hygroscopic when dry.

We have discovered that the amount of urea or urea derivative which mustbe added to the glue substance to obtain the desirable properties varieswith the grade of glue, the higher grade glues requiring largerproportions of the modifyto ten per cent by weight of urea will notbecome tacky although the atmosphere may be very moist or humid.

We have also iound that a mixture of urea and calcium nitrate, forexample, from two and one-half per cent to twenty per cent 01 thecommercial mixture of equal parts of these two sub stances which isknown as Calurea, may be substituted for pure or commercial urea. Theuse of a-mixture of calcium nitrate and urea permits the preparation ofa glue having a greater de- Gummed tape, for example, having a coatingwithout adversely afiecting the original flexibility and the promptremoistening properties of the glue coating. The glue coating will notabsorb. suflicient moisture from the atmosphere in humid weather tocause the glue coating to become tacky.

We claim: 1. Dry animal glue consisting of animal glue and from two andone-half per cent to ten per cent urea, the urea imparting to the gluethe properties of having a prompt remoistening value and a rapidresetting quality, but being insufiicient to impart tothe glue theproperty of being hygroscopic when dry.

2. Dry animal glue consisting of animal glue and from two and one-halfper cent to ten per cent of a mixture 0! equal parts of urea and calciumnitrate, the reagent imparting to the glue the properties of having aprompt remoistening value and a rapid resetting quality but beinginsumcient to impart to the glue the property of being hygroscopic whendry.

3. A dried glue composition consisting of animal glue and from two andone-half per cent to ten per cent of a reagent selected from the groupconsisting of urea, biuret and a mixture of equal amounts of urea andbiuret, the amount 0! reagent 'being sufllcient to impart promptremoistening values and a rapid resetting quality but being insuillcientto impart to the glue the property of being hygroscopic when dry.

4. A dried non-hygroscopic glue composition consisting as the essentialingredients glue and a reagent selected from the group consisting ofurea, biuret and a mixture of about equal amounts of urea and calciumnitrate, the amount of the reagent being present not in excess of about10% but in sufilcient amount to impart remoistening values and a rapidsetting quality.

5. A dried glue composition consisting of animal glue and from two andone-half to ten per cent biuret, the biuret imparting to the glue theproperties of having a prompt remoistening value and a rapid resettingquality but being insumcient to impart to the glue the property of beinghygroscopic when dry.

EDWARD F. CHRISTOPHER. FRANK L. DE BEUKELAER.

7 Patent No. 2,265,114.14;-

CERTIFICATE OF CORRECTION" December 9, l9LLl.

EDWARD F. CHRISTOPHER, ET AL.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows{ Page 2,sec-- 0nd column, line- 5, claim 5, for "biur-et" read -calciumnitrate-; and

that the said Letters Patent should be read with this correction thereinthat the same may conform to the record of the case in the PatentOffice.

Signed and sealed this 27th ,day of January, A. D. 1914.2.

. Henry Van Arsdale, (Seal) Acting Commissioner of Pa

